Bisexual Populations Research Articles

A discussion of bisexual populations with Wolbachia infection as an evolution algebra

In this paper, Wolbachia infection in a bisexual and diploid population with a fixed cytoplasmic incompatibility rate w and maternal transmission rate d is studied as an evolution algebra. As the cytoplasmic incompatibility (CI) of the population causes deaths in the offspring, the evolution algebra of this model is not baric, and is a dibaric algebra if and only if the cytoplasmic incompatibility rate w is 1 and d = 1 . The idempotent elements are given in terms of d and w. Moreover, this algebra has no absolute nilpotent elements when CI expression w ≠ 1 .

Substance Use and Adverse Mental Health Disparities Between Heterosexual and Sexual Minority Service Members in the U.S. Military.

Nationally representative studies have shown that lesbian, gay, and bisexual adults have higher levels of substance use than heterosexual adults. In the military, substance use is often associated with adverse mental health outcomes and is often comorbid with other mental health conditions and adverse or harmful behaviors. Few military studies to date have comprehensively examined the relationship between sexual orientation, mental health, and substance use. Data from the 2018 Health-Related Behaviors Survey (n = 17,166) were used. Univariate and multivariable logistic regression models were used to examine the association between sexual orientation and substance use. Regression models were also used to examine whether measures of mental health moderate the relationship between sexual orientation and substance use. Compared to heterosexual individuals, lesbian and gay individuals were more likely to engage in illicit drug use (adjusted odds ratio = 3.27; 95% CI, 1.45 to 7.36). Bisexual individuals were more likely to binge drink (adjusted odds ratio = 1.37; 95% CI, 1.08 to 1.74). Individuals with moderate or serious psychological distress were more likely to report binge drinking or smoking tobacco. Individuals with serious psychological distress were more likely to use illicit drugs. None of the interactions tested in this study were statistically significant. Substance use in the military was more likely among sexual minority individuals compared to heterosexual individuals. These findings reflect the patterns of substance use seen in the general population. Increased levels of psychological distress were associated with both the lesbian, gay, and bisexual population in this study and self-reported substance use behaviors. Further investigation of health disparities by sexual orientation may inform more efficacious treatment and prevention programs.

Trends in psychosocial research on LGBTIQ+ populations in Latin America: Findings, challenges, and concerns

AbstractPsychosocial research on lesbian, gay, bisexual, transgender, intersex, and queer (LGBTIQ+) populations from Latin America is relatively recent. Initially, research focused mainly on prejudice, using qualitative techniques. Studies on LGBTIQ+ populations, using more sophisticated psychosocial theories such as those of Herek or Meyer, began in the mid‐1990s. This study deals with surveys and scales based on non‐probabilistic samples, LGBTIQ+ populations being the first studied. In the early 2000s, queer and/or LGBTIQ+ theories were introduced, and research has been much more interdisciplinary. This paper describes the theoretical frameworks used in LGBTIQ+ research in Latin America and examines distinctions in the findings from Mexico, Colombia, Chile, Argentina, and Brazil. Future research must involve cross‐cultural studies, systematic or scoping reviews, and studies on non‐binary populations. Finally, the conditions for reimaging LGBTIQ+ research in Latin America are discussed.

The number of artemia bottom cysts (Artemia Leach, 1819) in different hyperhaline lakes of the Altai territory

Artemia cysts are economically significant. One of the components of the reserve is the biomass of artemia cysts submerged to the bottom. 22 hyperhaline lakes of the Altai Territory were studied in 2018–2021. It was found that artemia lived in all the studied lakes, including bisexual populations in 4 lakes, and parthenogenetic populations in 18. The lakes were conditionally divided into 5 groups. 1192 soil samples were selected and processed. The types of sediments were conditionally divided into 6 groups depending on the dominant particles. The dependence of the concentration of bottom artemia cysts on the type of sediments was revealed (r = 0.289, p = 0.001, n = 732). It is determined that the concentration of cysts does not depend on the salinity of the water in the lake, with the same salinity, the density of cysts varies from 0 to several million depending on the type of sediments. The dependence of the concentration of bottom cysts in the summer period on the selected group of lakes was established (r = 0.817, p = 0.1, n = 5). In brine lakes the minimum concentration was observed in spring, in Deep-water and Medium-deep lakes the maximum was observed in summer, in Shallow brine lakes — in autumn. In group of lakes “Shallow, salt precipitates“ and “Drying up in summer” lakes a decrease in the concentration of cysts at the bottom was noted from spring to autumn. The influence of the depth of occurrence on the density of artemia cysts in silt sediments has been studied: in Maloe Yarovoye Lake 63% is in the upper layer, in Kulundinskoye Lake the highest density is in a layer of 5–10 cm, in Bolshoe Yarovoye Lake cysts are evenly distributed in viscous silt at a depth of 5 to 20 cm. The change in the concentration of bottom cysts in autumn and subsequent spring was analyzed to identify the proportion of cysts that have risen from the bottom. Up to 98% of cysts float in Shallow lakes, 4–62% in Deep and Medium-deep lakes.

Intimate Partner Violence Victimization and Perpetration among Lesbians, Gays, and Bisexuals

Intimate partner violence (IPV) is a global health concern that profoundly affects not only heterosexual but also lesbian, gay, and bisexual (LGB) populations. Although studies conducted outside Norway have reported similar prevalence rates of IPV in heterosexual and LGB relationships, no published studies from Norway, whether academic or from nongovernmental organizations, have focused specifically on IPV prevalence rates in the LGB population. One reason might be the absence of a standardized tool to measure IPV. In this study, as researchers with backgrounds in social psychology, violence and minority studies, we firstly aim to evaluate the validity of the Revised Conflict Tactics Scale (CTS-R) in understanding the intimate partner violence experiences of LGB individuals. Secondly, we investigate how common various forms of perpetration and victimization are within the LGB community, specifically looking at psychological aggression, physical assault, and sexual coercion. We are also interested in whether there are any differences in the experiences of these forms of violence based on sexual orientation. To conduct this research, we studied 285 LGB individuals in Norway, aged between 18 and 64 (mean age = 31.80 years). The results of a correlation analysis revealed that all types of victimization from and perpetration of violence are positively and strongly associated. Chi-square tests indicated that there was no significant difference among LGB individuals in psychological and physical victimization or perpetration. However, gay individuals reported significantly higher sexual IPV victimization and perpetration than lesbian and bisexual individuals. Overall, we suggest that the CTS-R has satisfactory construct validity and effectively helps gauge psychological, physical, and sexual IPV in the LGB population. Moreover, we conclude that psychological, physical, and sexual IPV perpetration and victimization are prevalent in LGB relationships in Norway, and thus, that LGB IPV warrants further investigation into its antecedents and consequences.

A new sexually dimorphic Diploechiniscus species (Tardigrada: Echiniscidae) from Calvert Island (British Columbia, Canada)

An important, but generally overlooked source in intraspecific variability of characters used in tardigrades taxonomy is sexual dimorphism. Dioecious tardigrades species with unisexual or bisexual populations are common, but external sexual dimorphism is rarely observed. The discovery and integrative analysis of a Diploechiniscus species population with high sexual dimorphism from Calvert Island (Canada) has allowed its description as a new species. Diploechiniscus dimorphus n. sp. is characterized by a different chaetotaxy in males and females, and by enlarged cephalic sensory appendages in the males. The discovery of this new species shows that it is important to consider sexual dimorphism as a source of intraspecific variability in tardigrade taxonomy due to its implications on the use of traits commonly used to delineate species such as chaetotaxy. Lastly, the finding of individuals of Diploechiniscus horningi ( Schuster and Grigarick, 1971 ), a species previously synonymized with Diploechiniscus oihonnae ( Richters, 1903 ), allows us to prove that it is genetically a separate species and to reinstate it.

Health Behaviors and Experiences of LGBTQ + Individuals during 2022 Mpox Outbreak: Findings from the QVax Study.

The 2022 global outbreak of Mpox (formerly named Monkeypox) disproportionately impacted lesbian, gay, bisexual, transgender, and queer (LGBTQ+) populations, with a significant impact on sexual minority men. A cross-sectional survey was conducted among LGBTQ + adults living in New Jersey and New York to examine vaccination behaviors for Mpox. We sought out to understand the health experiences and behaviors of the population during the initial outbreak. This analysis included a subset of participants (n = 253) who completed the survey after the onset of the Mpox outbreak in May 2022. We examined awareness of and concerns about Mpox, willingness to vaccinate, as well as vaccination access and vaccination uptake. Our findings indicate that white, cisgender, gay men, as well as employed individuals, had the highest rates of vaccination for Mpox. Those with higher levels of concern about the virus were both more likely to be vaccinated and to report difficulty securing an appointment. Overall, our findings reinforce the health disparities in the population, demonstrating as with many other health conditions that white and economically stable individuals have advantages in accessing care.

Occupational Health, Psychosocial Risks and Prevention Factors in Lesbian, Gay, Bisexual, Trans, Queer, Intersex, Asexual, and Other Populations: A Narrative Review

Despite advances in legislation and social attitudes, workplace discrimination against sexual and gender minority populations remains prevalent, posing significant psychosocial risks. This study aims to explore the occupational health challenges faced by LGBTQIA+ populations, examining factors of discrimination, support, and prevention strategies. Methods: A narrative review of articles from the Scopus, PubMed, and Web of Science databases was carried out, focusing on studies published between 2011 and 2024. Articles in English, Spanish, and Portuguese were considered. Results: 359 studies were identified, and 11 articles were selected for analysis. The findings reveal pervasive discrimination experienced by LGBTQIA+ workers in the workplace, impacting their mental health and job satisfaction. Factors influencing disclosure of sexual or gender identity at work were identified, including workplace characteristics and anti-discrimination policies. Conclusions: Promoting inclusive and supportive work environments is crucial to the well-being of LGBTQIA+ employees. Recommendations include strengthening anti-discrimination protections, improving education and training on LGBTQIA+ issues, and promoting explicit communication about support and equality. Despite progress, more research is needed to address gaps in understanding and effectively promote the occupational health of sexual and gender minority populations.

Examining alcohol use disorder treatment utilization in lesbian, gay, and bisexual populations through the Behavioral Model for Vulnerable Populations

AbstractThere is significant need for alcohol use disorder (AUD) treatment among lesbian, gay, and bisexual (LGB) individuals. Furthermore, utilization among LGB individuals is below indicated treatment need due to interpersonal and structural barriers. A hierarchical logistic regression examined relationships among perceived public, interpersonal, and healthcare discrimination in relation to treatment utilization using secondary data from a subsample of the 2012–2013 National Epidemiologic Survey on Alcohol and Related Conditions‐III. Findings indicate that increased public and interpersonal discrimination is associated with higher likelihood of healthcare discrimination. Healthcare discrimination predicted higher AUD treatment use. Clinical implications and recommendations for future research are discussed.

Addressing the Health Needs of LGBTQ Persons in Medical Curricula: A Review of Educational Programs.

Given the vulnerability of and the importance of caring for the specific health care needs of the growing lesbian, gay, bisexual, transgender, and queer (LGBTQ) population, the authors attempted to identify all educational interventions in psychiatric settings with quantitative outcomes targeting medical students, residents, and physicians in postgraduate settings. To gain insight from other disciplines that have published research in this area, a second objective was to review studies in teaching in those other disciplines. The authors sought to describe the methods of selected studies. The authors searched the published English-language literature indexed in PubMed, EMBASE, and PsycINFO using key terms for health care education concerning LGBTQ populations. The authors described and critically appraised studies with quantitative outcomes designed to enhance knowledge, skills, and attitudes in treating the LGBTQ community. Of the 15 trials identified, 10 included medical students, 4 included internal medicine residents or medical school faculty, and 1 included oncologists. We did not find any randomized controlled trials or controlled nonrandomized trials of curricula dedicated to teaching learners in psychiatry. All of the studies included a presurvey, followed by an educational intervention and then a postsurvey assessment. The educational interventions, outcome measures, and quality of studies varied widely. Four studies enrolled self-identified members of the LGBTQ community as trainers and facilitators of the educational interventions. The lack of high-quality controlled studies indicates the need to develop evidence-based curricula to support the education of the psychiatric workforce to provide for the special needs of LGBTQ persons.

Sexual outcomes in men who have sex with men who underwent radical prostatectomy.

Sexual difficulties are a recognized consequence of prostate cancer (PCa) treatments. An estimated one in three men who have sex with men (MSM) receive PCa a diagnosis during their lifetime. MSM may experience all types of sexual dysfunction as reported in men who have sex with women (MSW), along with a number of more specific bothersome problems. This systematic literature review aims to evaluate sexual outcomes in MSM who have undergone radical prostatectomy (RP). A systematic review was carried out following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The searches were made using relevant keywords in the PubMed, Scopus, and Web of Science databases, thus including the whole literature from January 2000 to November 2023. Studies which did not allow to retrieve data on sexual outcomes on MSM treated with RP for PCa were excluded. Data on sexual outcomes and health-related quality of life (HRQoL) were retrieved, mostly including changes in libido, erectile function, ejaculatory disorders, orgasm, climacturia, changes in role-in-sex identity, changes in sexual partnerships, and the presence of painful receptive anal intercourses (AI). CRD42024502592. Six articles met the inclusion criteria. In total, data of 260 patients were analyzed. Three main themes emerged: (a) MSM may experience specific sexual dysfunctions due to the different dynamics of their intimacy; (b) the lack of tool validated on gay and bisexual population to assess sexual outcomes (c) the need for a tailored approach that also takes into account sexual orientation throughout the oncological journey. MSM undergoing RP may experience similar sexual problems as MSW. Painful AI should be considered a potential post-operative adverse outcome in MSM. Future studies should prioritize validating a questionnaire that explores AI. Healthcare providers should adopt a tailored approach that takes into account sexual orientation throughout the cancer journey.

Risk for Experiencing Psychological and Sexual Abuse On- and Offline: A Comparison of Bisexual, Gay/Lesbian, and Heterosexual Women and Men.

Dating abuse research on lesbian, gay, and bisexual (LGB) populations tends to aggregate LGB participants for comparisons with heterosexuals and often excludes non-assaultive dating abuse and abuse that takes place on online dating applications. In the present study, we used the Pew Research Center's 2019 American Trends Panel Wave 56 dataset (N = 4712) to compare ever experiencing several types of non-assaultive on- and offline dating abuse between bisexual women (n = 402), lesbian women (n = 207), heterosexual women (n = 1802), bisexual men (n = 225), gay men (n = 575), and heterosexual men (n = 1501). We found that gay men and bisexual women generally had the greatest odds of experiencing online dating abuse. Bisexual and heterosexual women had the greatest odds of experiencing some offline abuse (e.g., being touched in an uncomfortable way), but gay men and bisexual women and men had the greatest odds of experiencing other offline abuse (e.g., having their contact information or a sexual image of them shared non-consensually). Findings highlight how assessments of non-assaultive dating abuse in on- and offline contexts via analyses of more specified gender/sex/ual identity groups can broaden understandings of dating abuse victimization, especially among sexual minority populations.

Del androcentrismo hacia un nuevo enfoque de la transversalización de la perspectiva de género a través de la Corte Interamericana

The primary goal of this research is to introduce a new approach to mainstreaming gender perspective, which includes not only women and girls but also the lesbian, gay, bisexual, transgender, and intersex (LGBTI) population. The study begins by examining the androcentric view of society, which has fostered its heteronormativity and patriarchal system. It then explores the evolution of the concepts of gender perspective and gender identity. Finally, the analysis evaluates judgments and advisory opinions issued by the Inter-American Court of Human Rights (IACHR) on matters concerning non-discrimination, sexual orientation, family, work, and equal protection under the law. These legal decisions establish reparative actions to safeguard and advance the rights of vulnerable groups. The study also aims to underscore the reparative measures concerning non-repetition guarantees, which the Inter-American Court advocates to promote mechanisms and public policies that States must adopt to overcome barriers of discrimination and social stigma that continue to impact Latin American societies.

A Scoping Review of Trends in the Size of Lesbian, Gay, and Bisexual Tobacco Use Disparities, 1996-2020, United States and Canada.

Purpose: Tobacco use is a major health disparity for lesbian, gay, bisexual, and transgender (LGBT) populations compared with heterosexual/cisgender populations. In this scoping review, we aimed to determine if LGBT tobacco use disparities are improving or worsening over time and if trends in disparities differed across subgroups. Methods: We included articles that longitudinally explored youth and adult LGB tobacco use in the United States and Canada after searching four databases and capturing records through July 2022. Two reviewers independently screened the title/abstract and full text of 2326 and 45 articles, respectively. Eleven articles from 18 larger assessments met inclusion criteria, spanning data collection from 1996 to 2020. Results: All studies consistently demonstrated tobacco disparities for LGB populations. No articles examined longitudinal transgender tobacco disparities. Most studies focused on smoking combustible cigarettes. Disparities in heavy or daily use for all LGB youth subgroups compared with heterosexual samples appear to be shrinking longitudinally. Results for early-onset, current, and lifetime smoking were less consistent. Adult evidence was relatively sparse; however, after 2010, studies show diminishing disparities over time, except for current smoking by bisexual women. Conclusions: Large tobacco use disparities persist for LGB populations, although the size of disparities may be decreasing for some groups. Initiatives for lesbian and bisexual women and girls should be prioritized, in addition to interventions addressing LGB smoking broadly. Surveillance instruments should uniformly and consistently assess LGBT identities and tobacco use behaviors.

Trends in simultaneous alcohol and marijuana use among US adult recent drinkers: Differences by sexual identity, 2015–2020

Simultaneous alcohol and marijuana (SAM) use has become increasingly prevalent among young adult populations. Moreover, lesbian, gay, and bisexual populations are at increased risk for substance use initiation. To date, little research has examined trends in SAM use by sexual identity. This study aimed to investigate trends in SAM use among recent drinkers using nationally representative data. Pooled data from the 2015–2019 and 2020 National Survey on Drug Use and Health (NSDUH) were examined among 120,061 individuals (5.75% LGB) 18 years or older who reported using alcohol in the past month. Given the methodological changes in the study design, we analyzed these waves separately. Covariates included age, race, biological sex, sexual identity, rurality, and past month use of tobacco. Weighted logistic regression models and trend analyses were conducted. An estimated 11,952 of the sample reported using marijuana during their last episode of drinking. A significant linear trend (b = 0.12) of increasing SAM use among recent drinkers from 2015 to 2019. When compared to heterosexual individuals, lesbian or gay (aPR: 1.44, 95% CI 1.26, 1.63) and bisexual (aPR: 1.92, 95% CI 1.77, 2.09) individuals were more likely to report SAM use. Among the entire sample, females had a lower risk of SAM use than males (aPR: 0.68, 95% CI 0.65, 0.72). For 2020, a total of 25,679 adults 18 years or older participated in the survey, with 2622 identifying as LGB and 54.1% reporting past month alcohol use. An estimated 1503 individuals reported SAM use. Consistent with our findings, of those reporting past month alcohol use, LGB populations were at higher risk for SAM use, with gay individuals (aPR: 1.59, 95% CI 1.11, 2.30) at increased risk and bisexual individuals having higher risk (aPR: 2.12, 95% CI 1.73, 2.60). SAM use among individuals presents several critical health concerns, especially for at-risk populations. Findings from the present study can inform tailored interventions to reduce minority stress and stigmatized identities are needed.

Sexual Orientation and Cervical Cancer Screening Among Cisgender Women

Lesbian, gay, and bisexual populations face barriers accessing health care in Chicago, Illinois. To describe the prevalence of up-to-date cervical cancer screening among lesbian, gay, and bisexual vs heterosexual cisgender women in Chicago. This retrospective, cross-sectional, population-based study of cisgender women residing in Chicago was completed from 2020 to 2022 using data from the Healthy Chicago Survey, which is conducted annually by the Chicago Department of Public Health. Participants included cisgender women aged 25 to 64 years with no history of hysterectomy. Respondents who self-identified as lesbian, gay, or bisexual or other than straight, lesbian, or bisexual were coded as lesbian, gay, or bisexual (LGB). Respondents who self-identified as straight were coded as heterosexual. Those who reported having a Papanicolaou test within the past 3 years were considered up-to-date with cervical cancer screening. Data analysis was performed from June to October 2023. The primary exposure was sexual orientation. Covariates included age, income level, race, ethnicity, having a primary care practitioner (PCP), and insurance coverage. Prevalence ratios (PRs), log-based regression models, and interaction analysis were used to describe the association of sexual orientation with up-to-date screening. The sample included 5167 cisgender women (447 LGB and 4720 heterosexual), aged 25 to 64 years, with no history of hysterectomy. Among LGB cisgender women, 318 (71.14%) reported previous cervical cancer screening compared with 3632 (76.95%) heterosexual cisgender women. The prevalence of up-to-date screening was 10% lower in the LGB group compared with the heterosexual group (PR, 0.90; 95% CI, 0.82-1.00). In regression analysis, having a PCP (PR, 1.43; 95% CI, 1.29-1.59) was associated with up-to-date screening. In interaction analysis, LGB cisgender women with a PCP were 93% more likely to be up-to-date compared with those without a PCP (PR, 1.93; 95% CI, 1.37-2.72). In this cross-sectional study of cervical cancer screening rates between the heterosexual and LGB populations in Chicago, up-to-date cervical cancer screening was associated with having a PCP, regardless of sexual orientation, but this association was greater for LGB individuals. Although LGB populations were less likely to be screened, this disparity may be reduced with more consistent health care access and established care with PCPs.

LGBTQ+ individuals are not explicitly represented in emergency medicine simulation curricula

Background Medical educational societies have emphasized the inclusion of marginalized populations, including the lesbian, gay, bisexual, transgender and queer (LGBTQ+) population, in educational curricula. Lack of inclusion can contribute to health inequality and mistreatment due to unconscious bias. Little didactic time is spent on the care of LGBTQ+ individuals in emergency medicine (EM) curricula. Simulation based medical education can be a helpful pedagogy in teaching cross-cultural care and communication skills. In this study, we sought to determine the representation of the LGBTQ+ population in EM simulation curricula. We also sought to determine if representations of the LGBTQ+ population depicted stigmatized behavior. Methods We reviewed 971 scenarios from six simulation case banks for LGBTQ+ representation. Frequency distributions were determined for major demographic variables. Chi-Squared or Fisher’s Exact Test, depending on the cell counts, were used to determine if relationships existed between LGBTQ+ representation and bank type, author type, and stigmatized behavior. Results Of the 971 scenarios reviewed, eight (0.82%) scenarios explicitly represented LGBTQ+ patients, 319 (32.85%) represented heterosexual patients, and the remaining 644 (66.32%) did not specify these patient characteristics. All cases representing LGBTQ+ patients were found in institutional case banks. Three of the eight cases depicted stigmatized behavior. Conclusions LGBTQ+ individuals are not typically explicitly represented in EM simulation curricula. LGBTQ+ individuals should be more explicitly represented to reduce stigma, allow EM trainees to practice using gender affirming language, address health conditions affecting the LGBTQ+ population, and address possible bias when treating LGBTQ+ patients.

Family Support, Outness, and Psychological Well-Being in LGBTQ+ Adult Children of Immigrants

Researchers have documented mental health issues of Lesbian, Gay, Bisexual, Transgender, and Queer (LGBTQ+) populations. Those with multiple minority identities may face greater mental health concerns due to minority stress. Little research has examined the mental health of LGBTQ+ adult children of immigrants. The objective of this study was to determine if family support, as measured by interpersonal and environmental microaggressions and microaffirmations, predicted levels of outness and levels of psychological well-being in LGBTQ+ adult children of immigrants and to assess whether family support was a moderator in the relationship between outness and well-being. 109 participants completed an online survey that included three measures and demographic information. Multiple regression showed that family support did not predict outness in LGBTQ+ adult children of immigrants, but environmental microaffirmations predicted psychological well-being and environmental microaggressions moderated the relationship between outness and psychological well-being. We discuss implications for helping professionals and future directions for research.

INTIMATE PARTNER VIOLENCE AND THE THIRD GENDER

LGBTQIA+ community across the world has been fighting tooth and nail for their rights and establishing their legal identity across the globe. From fighting for rights of equal opportunity to equal recognition of their capabilities, this community has seen it all. From one but huge victory by decriminalizing of Section 377 of IPC, to claiming recognition to same- sex marriage in India, we have come a long way. Supreme Court in the petition for Same-Sex Marriage rights, it was well observed that it would hurdle the whole fraternity of Personal Laws. But what was completely out of picture during the debate of this petition was the Intimate Partner Violence (IPV). The lesbian, gay, and bisexual (LGB) population faces more difficult outcomes compared to the heterosexual population “across different life domains, including mental and physical health, subjective wellbeing, employment, poverty, homelessness, and social exclusion. IPV in the LGBTQ population has not been studied as frequently as in the heterosexual population.

Comparative Analysis of Bisexual and Parthenogenetic Populations in Haemaphysalis Longicornis.

Haemaphysalis longicornis, a three-host tick with a wide host range, is widely distributed in different countries and regions. It stands out among ticks due to its unique feature of having both parthenogenetic and bisexual populations. Despite their morphological resemblance, the characteristics of the parthenogenetic population have been overlooked. In this comprehensive study, we systematically compared the similarities and differences between these two populations. Our investigation revealed that the parthenogenetic H. longicornis, widely distributed in China, was found in ten provinces, surpassing the previously reported distribution. Notably, individuals from the parthenogenetic population exhibited a prolonged blood-feeding duration during the larval and nymph stages compared to their bisexual counterparts. Additionally, the life cycle of the parthenogenetic population was observed to be longer. A flow cytometry analysis indicated a DNA content ratio of approximately 2:3 between the bisexual and parthenogenetic populations. A phylogenetic analysis using whole mitochondrial genome sequences resulted in the separation of the phylogenetic tree into two distinct branches. A molecular analysis unveiled a consistent single T-base deletion at nucleotide 8497 in the parthenogenetic population compared to the bisexual population. Both populations displayed high viral infection capability and significant resistance to ivermectin. Intriguingly, despite these differences, the parthenogenetic population exhibited a similar life cycle to the bisexual population, retaining the ability to transmit pathogens such as Severe fever with thrombocytopenia syndrome virus (SFTSV) and Heartland Virus (HRTV). These findings contribute to a deeper understanding of the distinct characteristics and similarities between different populations of H. longicornis, laying the foundation for future research in this field.